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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Context: We have a backend where v32i1 is a Legal type, but the storage for v32i1 is not 32-bits/uses a different instruction sequence.<o:p></o:p></p>
<p class="MsoNormal">We ran into an issue because combineLoadToOperationType changed v32i1 loads into i32 loads, so a sequence like:<o:p></o:p></p>
<p class="MsoNormal">define void @bits(<32 x i1>* %A, <32 x i1>* %B) {<o:p></o:p></p>
<p class="MsoNormal"> %a = load <32 x i1>, <32 x i1>* %A<o:p></o:p></p>
<p class="MsoNormal"> store <32 x i1> %a, <32 x i1>* %B<o:p></o:p></p>
<p class="MsoNormal"> ret void<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is transformed to:<o:p></o:p></p>
<p class="MsoNormal">define void @bits(<32 x i1>* %A, <32 x i1>* %B) {<o:p></o:p></p>
<p class="MsoNormal"> %1 = bitcast <32 x i1>* %A to i32*<o:p></o:p></p>
<p class="MsoNormal"> %a1 = load i32, i32* %1, align 4<o:p></o:p></p>
<p class="MsoNormal"> %2 = bitcast <32 x i1>* %B to i32*<o:p></o:p></p>
<p class="MsoNormal"> store i32 %a1, i32* %2, align 4<o:p></o:p></p>
<p class="MsoNormal"> ret void<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This looks to be intentional. <o:p></o:p></p>
<p class="MsoNormal">Is there a way to specify in the data-layout that v32i1 storage is not 32-bits?<o:p></o:p></p>
<p class="MsoNormal">Absent that, is there any other reliable way to retain the original vector loads/store without just disabling this part of InstCombine?<o:p></o:p></p>
<p class="MsoNormal">Or is it the backend’s responsibility to try and work with this?<o:p></o:p></p>
<p class="MsoNormal">Thanks!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Pete<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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